Method of and apparatus for purifying oil



y 1940- M. GAERTNER 7 7,399

METHOD OF AND APPARATUS FOR PURIFYING OIL Filed Sept. 25, 1937 5Sheets-Sheet 1 ATTORNEY.

' July 9, 1940.

M. GAERTNER METHOD OF AND APPARATUS FOR PURIFYING OIL Filed Sept. 25,1937' 5 Sheets-Sheet 2 INVENTOR. MOP/TZ SHEET/YER ATTORNEY.

METHOD OF AND APPARATUS FOR PURIFYING OIL Filed Sept. 25, 1937 5Sheets-Sheet} INVENTOR. MGR/T2 GAERT/VER BY (1. 0 M

ATTORNEY.

J 9, 1940 M. GAERTNER 2,207,399

METHOD OF AND APPARATUS FOR PURIFYING' OIL Filed Sept. 25, 1937 Q 5 Sheets-Sheet me fig m2 1NVENTO&

MOR/ TZ 6H ER T/YE BY ATTORNEY.

Patented July 9, 1940 STATES 2,201,399 METHOD OF AND APPARATUS FGRMoritz Gaertner, New York, N. Y.

Application September 25, 1937, Serial No. 165,658

11 Claims.

The present invention relates to the art of purifying oil, and, moreparticularly, to an improved process of and apparatus for purifyinglubricating oil.

As those skilled in the art know, it is one of the most importantrequirements in the construction and operation of machinery, to provideadequate lubrication and an adequate supply of lubricants to allsurfaces having a sliding displacement with respect to each other. Inengi-' neering practice it was customary to provide a substantiallyclosed circulation of the liquid lubricants such as oil through thevarious parts of the machinery requiring lubrication, the circulationbeing maintained by means of a pump. If the circulatory system wasproperly designed and operated, the parts to be lubricated have beencontinuously provided with a satisfactory and sufiicient supply ofliquid lubricants.

Although a system of the described character strongly felt in theoperation of internal com-' bustion engines, such as automotive engineswhere the problem was greatly aggravated by the high temperatures andpressures to which the lubricating oil was subjected during theoperation of the engine.

Experiments have shown that the composition of the sludge accumulatingin oil circulating systems of various internal combustion engines issubjected to very wide variations. In addition to this, all sludgesconsist of complex mixtures of various substances finding their way intothe lubricating system or produced from the oil during the conditions ofoperation, such as road dust and other impurities contained in the airdelivered to the combustion chambers, moisture, metallic particles ofthe sliding surfaces, and the like. Thus, a typical sludge obtained fromthe average of 225 samples taken from the crank cases of automotiveengines was found to contain the following substances:

' 'Dilutinn 14.6000 Insolubles .4840 Asphaltenes .0640 Carbon- .2740Ash--- .1515 Iron oxide .1075 Copper oxide .0035 Tin oxide .0051 Leadoxide .0012 Metals .1178 Silica .0167 Silica from iron .0122 Othercompounds .0169

This table clearly indicates that the average sludge found incontaminated lubricating oils is of a highly complex character andcontains a wide variety of harmful ingredients. In addition tothe aboveimpurities, sulphur-containing acids can generally be found in allcrank-case drainings. This can come from traces of sulphur remaining inthe finished oil or the finished gasoline, which may form gums and otherdetrimental impurities. Fatty acids found in oil drainings are theresult apparently of oxidation and while they are greasy and improve theadhesive quality or oiliness of the oil; they combine very rapidly withthe water and oil to form soaps and emulsions. The fatty acids contained.in the sludge consist largely of oleic acid with additions of formic,acetic and butyric acids. The complexity of the average sludge makes iteasily understood why the purification of lubricating oil is connectedwith such great difliculties.

The accumulation of sludge and of water'in the circulatory lubricatingsystem of various engines was soon recognized to be the principal reasonof excessive wear on'the various rotating and reciprocating parts. Thecustomary procedure was to pass the impure or contaminated oil through amass of foraminous material; such as fabric, cotton fiber, paper pulp,fullerfs earth, etc., etc. These foraminous materials were contained ina filter which was connected in series with all' or with a portion ofthe oil stream. These conventional filters generally comprised one orsometimes a plurality'of such foraminous members or material havingopenings. P res,

the impurities without blocking the passage of the pure oil. Filters ofthis type have become an integral part of most engines and particularlyof internal combustion engines. However, the conventional filters didnot provide a satisfactory solution of the problem. First of all, thevery ability of the filter surfaces or foramina to retain smallparticles of impurities caused these particles to be permanentlyretained therein, to clog the openings and to soon completely stop theoperation and the efllciency of the filter. In most of the conventionalfilters in which a socalled filter cartridge was provided constituted ofporous cellulosic material, waste cotton and the like, the cartridgebecame practically useless after a short period of operation or after afew hundred miles. Of course, the filter cartridges were too expensivefor being discarded every few hundred miles, and have generally beenretained for at least 5 to 10,000 miles. cw, it has been ascertainedthat a filter cartridge which has been in use for such a length of time,did not only completely outlive its usefulness, but in fact provided anadded danger to the emciency of lubri cation in that the pressure of oilhas made a relatively wide passage through which the oil would streamunfiltered or clogging up the filter increased the pressure of oilcirculation whereby at times even particles previously caught andretained in the filter element were freed and returned into the oilcirculation where they caused a substantial danger to the machinery.Moreover, the operation of conventional foraminous filters was very slowin view of the restricted foraminous passages, so that a long time wasre quired to pass all of the oil of the circulatory system through thefilter. In the meantime the various impurities had ample time to becirculated in the oilstream and to be in contact with e ventionalfilters were also incapable of removing water from the oil and to breakup emulsions of water and oil. Although the various oil filters havebecome a standard part of almost all auto-' motive equipment, andfrequently excessive assertions have been made for this or that type offiltering element, the fact remains that up to the present day it wasfound to be practically impossible to obtain positive and satisfactoryrecourse, entailed considerable expense and has caused inconvenience'andloss of time. As a matter of fact, the expense involved in frequentlyhanging the oil was as highasto constitute fissures and the like,sufficiently small to retain a substantial portion of the totaloperating cost of the engine. However, the cost and trouble involved inthe frequent changing of the oil did,

not constitute all of the disadvantages of this conventional procedure.It has been found by experiments of various lubricating experts, thatthe oil which has been employed and circulated in the lubricating systemof anengine for a considable length of time, if the impurities andsludge gradually collected therein are continuously removed, actuallyincreases its lubricating power and efilciency in that certain chemicaland physical changes are taking part therein and the portions subject toready chemical decomposition under high temperatures and pressures havebeen already converted to sludge. By removing all of these impurities ina positive and satisfactory way, a stable lubricating oil of superiorquality and efficiency is obtained which is'capable of reducing frictionand engine wear to a minimum neverobtained heretofore "on a practicalscale. I

From the foregoing considerations, the importance, the gravity and thevexatious character of the problem will readily be appreciated. Althoughfrom time to time various suggestions and proposals have been made tosolve the outstanding problem, none, as far as I am aware, of thesesuggestions and proposals was completely satisfactory and successfulwhen carried into practice on a practical and commercial scale.

I have discovered that the problem may be solved in a remarkably simplemanner.

It is an object of the present invention to provide a method ofpurifying oil which is free from the disadvantages and inconveniences ofconventional oil treating methods.

It is another object of the invention to pro videa novel'and'improvedmethod of purifying lubricating ofls which dispenses with theinefficient, expensive, and detrimental foraminous elements ofconventional filtering methods and which employs a novel physicalprinciple.

. It isa further object of the invention to pro.-

vlde a novel and improved purifying method for viscous liquids .whichinvolves the application of acceleration, deceleration, selectivefriction, constrictlon, expansion and change of direction of a stream ofliquid for separating sludge and other impurities therefrom.

Still another object of my invention is to pro vide a novel purifyindesludging and improving method for the treatment of lubricating oil inwhich not the difference in size between the oil and sludge particlesbut the difference in other of their physical properties such asparticularly mass, molecular attraction and frictional coef ficient arerelied upon for the separation.

' Furthermore, it is an object of the invention to split a liquid streaminto an upper and a lower layer by means of differential and selectivefrictionand acceleration, the upper layer being constltuted .of liquidof increasing purity -ficwing above the lower layer of accumulatedimpurities .which due to their different acceleration, surfaceattraction andhigher specific .gravity will gradually drop throughdownward passages provided forthiswrposeintoasumpchamberandarepermanently withdrawn from the stream.

1 The invention also contemplates a novel oil purifier capable ofcarrying the method of the present invention into practice.

It isalso within contemplation of the pres ent invention to provide anovel and improved .oll purifying apparatus capable of handling a 75curves. undulating or corrugated channels for the substantial quantityofoil in a continuous flow which is simple in construction, satisfactoryand fool-proof in operation and which can be manufactured and sold on a.practicaland commercial scale at a low price.

Other and further objects and advantages of the invention will becomeapparent from the following'description, taken in conjunction with theaccompanying drawings, in which;

Fig. 1 illustrates a vertical sectional view of an oil purifier anddesludger embodying the principles of the present invention;

Fig. 2 depicts a fragmentary and perspective view having parts insection of one of the conical desludging members employed in thepurifier shown in Fig. 1;

Fig. 3 is a vertical sectional view, also fragmentary, of a portion ofthe conical desludging members indicating the fiow of oil therein;

Fig. 4 illustrates a similar view of a conical desludging member of amodified form;

Fig. 5 is a vertical sectional view of a modified oil purifier embodyingthe invention;

Fig. 6 shows a vertical section through another modified embodiment ofthe present invention into a combined desludger, dehydrator and Fig. 9depicts a section through a further modified form of the combineddesludger and dehydrator.

Broadly stated, according to the principles of my invention I establisha flow of the oil to be purified. I subject this flow to changes in themagnitude and the direction of its velocity. In view of the fact thatthe flow .of impure oil may be considered as a mixture of lighter andheavier particles such as particles of pure oil, particles of water, ofoil and water emulsion, particles of sludge of the most difierentcharacter, changes in the velocity of the flow and in its direction willafiect these particles of different specific weight and of differentfrictional coefficient in a different manner. Clearly, a. greater forceis necessary to start a heavier body or particle into an acceleratedmotion and it will take longer to retard its velocity than a lighterpartlcle.- In addition to this, of course, also the difference-of thecoefiicient of friction between the particles and the walls within whichthe flow is confined will be widely different for oil,'which has a verylow 00-.

. efficient of friction, forwater which has a considerably highercoefiicient of friction and the various types of sludges which generallypossess an extremely high .coemcient of friction and therefore greatersurface attraction. The result will be separation of the mass of impureoil'into its different constituents. The impurities havin a greaterspecific weight and a greater frictional resistance than the pure oilwill be generally retarded in their flow and may be gradually trappedand removed from theflow, as this will be explained hereinafter.

I have discovered that the change in the velocity of the flow is bestaccomplished by providing one or a plurality of channels for the flow ofimpure oil and by constricting and expanding said channels atpredetermined and preferably regular intervals. constriction of the flowwill cause increase in the velocity thereof while expansion of the flowwill decrease the velocity of the fiow. In addition to the variations inthe cross section of the flow, excellent results are obtained -bychanging the direction of the flow by providing flow at predeterminedintervals including complete reversal-of the direction of the flow atother, wider, intervals. The changes in the direction of the flow willaffect the velocity of the flow and in addition to this will greatlyincrease the selective effect of friction upon the sludge and oilparticles. Obviously, a flow which is constantly changing its directionis subjected to great frictional resistance by the walls o'fthe channelin which the flow is retained. Moreover, the change in direction andparticularly the complete reversal of the fiow will cause deflection,reflection and impact of the particles with consequent selective actionand precipitation in accordance withrents and of breaking up theemulsions of water and oil.

In practical operation, I prefer to provide the channels inpwhich theoil stream to be treated is to flow, in the form of conical surfaces orpartition walls between which the flow is confined. A

plurality of such partition walls may be provided and the flow may beconducted inbetween successively. I have found that by providingfiutings and corrugations of a concentric circular form in said conicalpartition walls, the desired periodical constriction and expansion ofthe flow will be readily obtained, while by alternately carrying flowdue to its different mass and frictional characteristics and are removedto a sludge chamber located in thelower portion of the apparatuswherefrom they can be removed at distant intervals.

Although the described structure provides the great advantages of greatsimplicity and facility to manufacture, and also requires but littlespace for the treatment of a predetermined quantity of oil, it is alsopossible to provide other practical forms of apparatus for the desiredconstriction, expansion and reversal of the flow for example, by'providing inclined parallel channels of a substantial length andconstituted of a plurality of smooth and inclined partition wallsbetween which the fiow is directed alternately in upward and downwarddirection. The principle .of operation remains the same, so long thebasic bodying my invention satisfactorily removes all of the solidimpurities such as the various forms of sludge, breaks up theundesirable emulsions, and

separates the water from the oil to be treated.

It is advisable in some cases to supplement the desludging action of thenovel oil purifier with a filter which removes the very finest remainingsolid particles which have not been removed by the effect ofthedifferential and selective accel-' eration and friction. In view of thefact that the oil introduced into the filter proper is already of asubstantial purity and contains only a rather insignificant amount ofresidual impurities, it

. filters. Moreover, since practically all of the water andof the sludgeand particularly the most dangerous abrasive impurities such as carbonand metallic particles are immediately and positively removed from theoil flow by the desludger or purifier, it is not necessary to pass allof'the oil flow'through 'the filter-but only a part thereof, as thoseskilled in the art will readily understand. The invention will now bemore fully described to those skilled in the art, reference being had tothe accompanying drawings.

Referring now more particularly to Fig. l of the drawings, a preferredembodiment of the invention is illustrated. Reference character Idenotes a tank, or container preferably integrally formed of metal. Tankis closed at the top by means of a cover or head 2 held in position bymeans of a clamping yoke 3. In the lower portion of tank I, I provide aconical partition wall 4 which separates the tank into an upper flowchamber and a lower sludge chamber. Conical partition wall 4 is providedwith a central opening 5 at the apex thereof. This opening 5' isprovided with a vertically depending flange 6 eral portions of alternateconical members, re-- downwardly projecting from an upwardly extendingconical member or partition wall I. At the upper end of the conicalmember, I provide an upwardly protruding flange i having a shoulder 8therein. adapted to receive and to hold another conical member ofsimilar character. As

it will be readily observed from the drawing, a plurality of suchconical members is'disposed in superimposed relation. Openings Ill andII are provided in the upper and the lower periphspectively, providing achannel or conical form 1 between each two successive conical membersanon sac periodically variable resistance to the fiow of the oil.Alternate corrugated conical members are provided with dependingfunnel-like extensions l3 opening one into another, thelowermost of saidfunnels protruding intoa vertical tube ll connected to the centerportion ;of the partition wall 4.. Each of said funnels may be provided.with an annular insert or member I! which provides a greatly restrictedportion or throat in said funnel. .This throat is capable' of offering arelatively low resistance against.

the downward 'fiow'o'f a quid'whereas it offers a very substantialresistance to the upward flow of a liquid substance. 'A perforatedpartition wall 16 is provided abovethe set of conical members and iscovered with a light-filter material l1. Ports II and I! are provided inthe tank for the introduction of oil to be purified and for thedischarge of piu'ifled and clean oil there-- from, respectively. Atthebottom of sludge] chamber 20, a port It is provided having a threadedstopper 22 inserted therein' which may be readily removed for thedischarge of sludge and of We water accumulated in the sludge chamrforated partition I. into a space 28 fromwhich;

From the preceding description, the operation of the improved oilpurifier will be readily understood by those skilled in the art. Whenoil is supplied under pressure to inlet port I8, for example byconnecting the purifier into the circulatory flow of lubricating oil inan internal mombustion engine, the impure oil will first fill up sludgechamber II through openings 21'. Due to the pressure of the oil feedingmeans of the engine, an oil stream or flow will be establishedbetweenthe corrugated plates 1. The oil will enter first openings ll ofthe lowermost plate,

- will flow upwards along the upper surface of said plate up to theupper end thereof where it will enter openings ll of the next plate l-iand will fiowdownwards along the upper surface thereof. It will be notedthat the oil will consecutively flow through all of the intervalsbetweenthe adjoining plates, all of said intervals being connected inseries. During this fiow the oil stream will be subjected to periodicalcompression and expansion due to the varying cross section providedbythe corrugations. This will be best observed from Fig. 2 which is anenlarged view of two such corrugated plates. In addition to thisperiodical compression and expansion, the direction of the flow will becompletely reversed at the end of each plate, and, as it will be bestobserved from Fig. 3, eddy currents will be set up and reflection anddeflection' of the stream willbe caused at each point where the crosssection of the fiow channel is suddenly changed. The cumulative effectof this frequent change in the magnitude and direction-of the broken upby the impact and frictional efi'ect of the flow and will be separatedinto its constitucuts. The eddy currents formed inthe corrugations orpock ts, assisted by the gravitational action will cause slow andgradual downward displacement of these undesirable particles along thesurface of plates 1 whereby these particles will finally arrive atfunnels liand will be discharged through sludge tube I I and openings 23therein into the deep sludge chamber displacing therefroma-corresponding quantity of untreated oil which is' lighter than theremoved impurities. Due to the depth of the sludge chamher and theunidirectional character of the throats in funnels IS, the impuritiescannotaccidentally be returned into the circulation but will rema npermanently trapped in the sludge chamber wherefrom they may be removedat remote intervals. It-is to be observed that the operation of thedevice'and the separation and downward displacement of the impurities isfurther assisted by the normal vibrations of the purifier in casethedeviceis mounted on an automobile or on a stationary engine. From thelast of the spaces between the corrugated mem-' bers or plates, thepurified-oil lwlll fiow by way of It in the periphery thereof to a ll inthe central portion of the container. From this chamber the oil willflow through a light filter cloth or felt I I and a perto the resistanceto the flow ofiered by an efiec-- tive conventional filter packembodying foraminous elements. In this connection, it may be observedthat the corrugations on members I and their counterparts in subsequentelements preferably vary in depth from the.entral portion to the outerperipheral portion thereof, so

that the passage between two opposite corrugations near the peripheralportion of the conical members will be considerably less than at thecentral portions. For example, a cone of about 5 inches in diameter willhave an approximate circumference of 16 inches so if the closest dis-'tance between two opposite corrugations is t; of an inch at thisportion, the cross section of the annular slit or opening so formedwould be about 1 square inch. The diameter of the lower and smallestcorrugation would be about 1 /2 inches and the circumference would beless than 5 inches so if the same distance of of an inch between the twoopposite corrugations were used, the cross section of the opening soformed would amount to only twenty to twenty-five per cent of theoutermost restriction. The distance, therefore, between the oppositecorrugations near the central portion is made sufliciently great tocompensate for this difference in total cross sectional area of theopening so formed. It is not necessary to have the exact cross sectionat the lower point equal to the cross sectional area of the opening atthe upper point as the frictional resistance on account of this smallercircumfercnce is much less. I

Although the total resistance to flow from inlet port 48 to chamber 26is not great and the rate of flow through this portion of .the devicemay be relatively rapid it still will effect the function of breaking upthe globules forming an emulsified mixture of on, water and solidimpurities and separating the water and the non-colloidal particlesfromtheentire oil stream.

Of course, corrugations or. fiutings ofdifierent form may be employed.Thus, instead of the smooth and circular type offiutings shown in Figs.1 to 3, it is also possible to employ fiutings 21 of the form depictedin Fig. 4' and having sharper edges, with equal or similar results;

Although the oil purified by means of the device embody g the principlesof the present invention can be directly introduced into the 111--bricating system of an internal combustion engine, in some cases it ispreferred to employ a foraminous filter for a finishing treatment of thepurified oil. In the present case this is permissible and can be carriedout without theus'ual disadvantages of such filters since the oil to befiltered is already almost completely pure and will provide satisfactoryservice for a relatively long time, as most of-the particles causingclogging of the foraminous elements have been pre- ,viously removed fromthe oil fiow. Likewise, the relative y small capacity of foraminouselements may be compensated for by connecting the foraminous filterelements only into a portion of the oil flow, which will not cause anytrouble, since the harmful abrasives and other impurities have alreadybeen removed. The combination of the desludger with the filter .willprovide an oil of such purity and lubricating uualities that it will notonly permanently retain the same 011 in a. constant and satisfactorycondition but even will improve the quality thereof, so that only smallquantities of lubricating oil have to be added to the supply. of oilfrom time to time to replace the amount which has been decomposed andused up during the normal operation of the engine.

Fig. 5 illustrates a modified embodiment of the invention embodying suchforaminous filtering elements. As the lower portion of the oiltreatingapparatus is'identical with that of the one shown in Fig. 1, and similarreference characters have been employed to denote corresponding parts,only the upper portion of the device, containing the filtering elements,will be 'described. From space 30 where the desludged' and. purifiedoilaccumulates, most of the oil is directly discharged and is introducedinto the circulation. A certain portion of the oil, how- 'ever, passesupwardly through the first of a plurality of filter packs 3| and aperforated partition 32 into a chamber 33. Partition 32 slopesdownwardly toward the central portionthereof and carries a dependingfunnel 34 which extends from the lower central portion of the partitionthrough the chamber 30 and into a tube 35 which 1 projects downwardlyinto the uppermost ofthe funnels l3. Any sediment or fine carbonparticles which tend to collect on the upper surface of the partition 32work gradually into the mouth of the funnel 34, due to the vibration ofthe device during the normal operation of the engine to which it isattached, and are conveyed downwardly to the lower portion of the sludgechamber 20. Space 33 above partition 32 is preferably divided by adeflecting member 31 .havmg openings 38 .in the periphery thereof sothat the oil passing from the first filter element must flow outwardlyto the periphery of the chamber. before it can pass upwardly to the nextsucceeding filter element. As it is illustrated in the drawing, aplurality of filter elements 3| are provided, each'nested in a dependingflange 39 of a succeeding filter'element and each of the perforatedpartitions slope downwardly to a central funnel similar in every respectto the funnel Each of these funnels projects for some distance into themouth of a preceding funnel so that all of the sludge and sediment from.each of the filters is conveyed from one funnel to the next andultimately through the tube 35 and' funnels 13 to the bottom of thechamber 20.

of the filter elements may be easily lifted out as a .unit fromcontainer l for replacement or cleaning. A lateral opening or port 4| ispro- The uppermost of the filter elements is provided with asuitablehandle 40- by means of which all vided at the upper end of thecontainer and is internally threaded to receive a suitable pipeconnection which conveys the filtered portion of the oil to the crossfitting 42 where it is united withthe main stream of oil passing to theengine. Preferably a by-pass pipe 43 containing a spring-operated checkvalve .4'4 directlyconnects the intake pipe 45 and the discharge pipe46,- check valve is constituted of a helical spring 31, pressing a ball48 against a suitable seat 49. The resistanceto fiow provided bythe'pressure of spring 41 is so much greater than the normal resistanceto the flow of oil. through the d sludger that there is no fiow of oilthrough the by-pass passage 43 unless the desludger is clogged. In thiscase, the increased pressure will opencheck valve against the pressur ofspring" so that the'ell will be directly ellduring the course of itsfiow through the device.

The impure oil entering at 45 is normally heated considerably abovenormal atmospheric temperatures due to its having been exposed to" hotoperating parts of the engine. Its viscosity and' accordingly itsresistance to flow has been lowered. The conicalmembers absorb thisheatand conduct it to the cylindrical member or container I from whichit is dissipated to the atmosphere by the fins.

Referring now to Figs. 6 to 8, a further modified embodiment of theinventionis illustrated. Reference character indicates a cylindricalcontainer having a lower integral end portion 52 and an upper removablehead 53 which may be readily secured in position by a clamping yoke 54;The lower end portion 52 is provided with a central internally threadedannular. boss 55 projecting outwardly therefrom for connection with thelubricating system of the engine. A similar annular boss 56 projectsinwardly to accommodate a tube 51 which projects upwardly through a deepsludge chamber 58 and a central opening 59 in a partition 80 and thebase member 62 of the desludger or purifier. Base megnber 82' is conicaland both this member and partition 60 are provided with downwardlyprojecting "peripheral flanges which fit snugly within a downwardlychamber 6| to the space between base member 52 and the first desludgerelement 4. This space is formed into a spiral passage 61 by means of aspiral strip 68 projecting downwardly from element 64 into contact withthe upper surface of base member 62. This structure will cause the oilto spiral upwardly and inwardly through the pa ssageri'l until it comesto the apex of the cone-' shaped .member 64 at which point. it passesthrough an opening II to an outwardly and downwardlyspiraling passage 68formed by upency of the heavier 'particles and globules of sludge to beseparated from the pure oil by the selective effect of acceleration anddeceleration and change in direction and friction, which in- A fiuencein a diiferent way the lighter particles of pure oil having a very lowcoefllcient of friction and the considerably heavier particles of waterand sludge particles and globules having a very high coeflicient offriction. Moreover, the heavier.

particles and the globules of sludge will be thrown against the metallicsurfaces'particularly at the points where the direction of the flowis-suddenly changed or even reversed, and broken by friction with thesesurfaces and by friction of one portion of the oil-with another..Generally speaking, the flow through these passages, is such that theoil adjacent any metallic-wall will fiow at a slower rate than oilremote ifrom one of the walls. Thus, thin sheets or laminae of oil willbe set up in the flowing liquid which will flow at progressievlyincreasing velocity from the metallic wall surfaces to the centralportion of the,

passages and the slipping of these laminae over each other will tend tofurther break up the emulsions of water and oil into their constituents.The heavier portions, such as water, solid particles and asphalteneswill gradually sink to the outer lower wall of the passage and onreaching the circumference of member 64 are drained off throughdownwardly extending funnel-shaped portions I3 which are integral withmember 64. Funnels 13 extend through openings 65 with sufficientclearance topermit oil to flow therearound, and also project throughpartition 60 so that the impurities will not be admixed with theincoming oil in chamber GI. From the ends of funnels II, the impuritiesare conveyed by a tube 14 to the lower portion of a deep sludge chamber58.

As it will be readily observed from Fig. 7, each of members 64 isprovided with two diametrically opposite funnel portions 13. p j

As illustrated: in Fig. 6, a plurality of desludger elements 64 isprovided each of which has a deep flange 63 projecting downwardly fromthe peripheral edge thereof and shouldered intermediate its length asindicated at I6, so that ,the elements may be nested one in'the otherand maintainedjn proper spacial relationship. Between each of themembers 84 and also nested within the depending flanges thereof, arepartitions I1, each of which is similar in structure to the base member62, each being provided with openings 66 spaced diametrically oppositein the peripheral edges thereof through which the funnels 13 of anysuperimposed element 64 may pro- Ject with suflicient clearance topermit the oil to pass upwardly therearound. Smaller peripheral openingsI5 may be provided in these partitions between openings 66 to permit thefree flow of oil through this portion of the partitions.

The uppermost of the desludger elements 64 is nested in a dependingflange I! of a conical cover member 18 which depending flange isprovided with a pair of internal shoulders 80 and BI upon the first ofwhich the lastof the elements 64 abuts and upon the last of which aconical partition 82 is tightly held. Partition 82 is similar in allrespects to the base member 62 except that the openings 83 in theperipheral edge thereof are smaller than the openings 66 in member 62.-

Since there is no funnel member such as I3 from a superimposed desludgerelement projecting through this opening, it is only sufflciently largefor the passage of oil therethrough. From openlugs 83, the oil passesupwardly through space 84 provided between conical partitions I2 andcover member II, A large opening 85 is provided at the apex of member."and the opening is surrounded by an upwardly extending annular flange 86which abuts a partition 81 adapted to close the first of a plurality offilter elements 88. -Filter' elements 88 are shown in the form ofaplurality of nested containers, each comprising a perfo- ;ratedmetallic partition 88 having a downwardly projecting internallyshouldered flange 90. In the first of these flanges, the partition 81 isnested .and in each subsequent flange the immediately preceding filterelement is nested.

Within each of jflle filter elements there is a filter pack 9I provided,and as shown in the draw- 8s, the thickness of these packs constantlyincreases from the first or lowermost of the elements to the last oruppermost thereof. Filter packs 9| are pressed snugly against the lowersurface of the perforated partitions 88 and are of such depth that oilspaces 82 are left between the lower surface of the filter pack and theuppersurface of the immediately preceding perforated partition 89. Inthe lowermost of the filter elements the oil space is formed between thepartition 81 and the filter pack 8|. Flange 85 is provided with openings93 for the passage of oil to 6 the space below partition 81 and withsmaller peripheral openings 84 in the partition 81 which permit thepassage of oilto the interior of the first filter element.

As this will be readily observed from Fig. 8,

15 filter packs 9i consist of one or more discs 85 of heavy fibrousmaterial, separated by sheets of porous cloth 98 such as canvas orflannel, for.

insuring thespreading of oil therebetween, while a heavy woven filtercloth 81 is positioned between 20 the uppermost of the fibrous discs ofeach pack and the perforated partition 89.

From the last of the filter elements 88, the oil enters a chamber 98between the uppermost of perforated partitions 89 and the head 58 ofconggs tainer 5|, from which it is discharged through a lateral opening89 to the points of use. The last of filter elements 88 is provided witha suitable handle I contained within chamber 88, so that the filterelements, together with the desludger 80 elements may be lifted'bodilyas a unit from the container when head 53 is removed.

The operation of this modified embodiment will be readily understood bythose skilled in the art from the precedingdescription and in view of 88the similarity of construction with the e'mbodiment of the inventionillustrated in Figs. 1 to 5;

The device is first filled with lubricating oil and during the operationthereof oil is supplied thereto through tube 57 to chamber 8I withoutdis- 40 turbing the sludge, water and other impurities accumulated inthe deeper portions of sludge chamber 58. From chamber 8|, the oilpasses upwardly through openings 88 while sludge, water and the heavier.of the solid particles from the 45 desludger element pass downwardlythrough fun-.

nels 13. As sludge accumulates in chamber 58, lubricant in the upperportion of this chamber is displaced to opening 58 into chamber 8! fromwhence it passes upwardly. to be purified in the 50 desludger and filterin the same manner as oil entering through tube 51. An opening IN isprovided in the base of container 5i for the drainage of sludge fromtime to time from the deep sludge chamber 58.

- ent invention depictedin Fig. 9 is much similar The further modifiedembodiment of the presto the embodiment shown in Figs. 6 to 8.Essentially, a desludger consisting of superimposed conical elementssimilar to the ones shown in Fig. 6 is provided, with the difierencethat the cones are inverted and the sludge funnels are located centrallythereof at the apex of the cones. In

this modified embodiment, the impure oil from the engine enters througha lateral-opening I02 5 intermediate-the end walls of the container andsufiiciently far above the bottom thereof to provide a deep sludgechamber I03 in the bottom of the .container. A partition I08 spaced wellup from the bottom of the container separate sludge 7 chamber I03 fromintake chamber I05. Partition I04 slopes downwardly from the centralportion thereof to the periphery and is provided with small openingsI08near the,circumference for the drainage of sludge tosludge chamberI03 and openings I01 near the central portion thereof tion of the sludgechamber to the intakechamber I05. 'Above partition I04 is a'conicalmember I08 having its apex in opposition to partition I00 and in contacttherewith. A downwardly projecting flange I00 surrounds an opening atthe apex of conical; member I08 and projects through a similar centralopening in partition I04. A' tube I I0 extends through the bottom wallof container 5| through sludge chamber I03 into the downward-yprojecting flange I08. Tube H0 is provided with large slots or openingsI l I at the bottom of chamber I03 but is otherwise closed except at itsupper open end. Openings II2 are provided at diametrically oppositepoints nearthe circumference of conical member I08 for the admission ofoil from intake chamber'l05 to the space II3 immediately above thismember. This space is divided into a continuous spiral passage similarto the spiral passages 81 and 88 described in connection with Fig. 6.The spiral passages are formed by downwardly projecting strips H8 whichare\ preferably integral with a conical member H4 which member is spacedfrom and extends parallel to member I08. The oil spirals downwardlythrough the passages so formed and there is a tendency of breaking uptheglobules containing the impurities by means of the selective anddifferential eflect of the acceleration and change of direction and dueto the difference of frictional coemcient'of pure oil and sludge, as

this has been described in the foregoing. As the oil reaches thecenterof space 8, the heavier impurities that have been broken up drainoff through the open end of the tube IIO while the remainder of the oilflows upwardly through a" central opening H9 in member H4 and thencethroughoutwardly spiraling passages in the space above partition 5,which spiral passages are carries a funnel portion I I1 which projectsdown wardly through an opening at the apex of member I'IE withsufficient clearance to permit oil to. flow upwardly therearound and italso projects with some clearance into the open upper end of tube I I0.The separated water and other impurities drain downwardly throughfunnels I I1 and through tube IIO to the lower portion of sludge chamberI03 without contaminating the portion of oil flowing upwardly throughthe desludger.'

As illustrated, a plurality of members identical with members II and H5are provided for completing the desludging and dehydrating process andtheir structure'and operation will be obvious from the portions alreadydescribed. From the uppermost of the desludger elements, the partiallypurified oil passes to a filter, of which only a portion is shown, butwhich is substantial y similar in structure to the one depicted 'in Fig.6. In the filter, the extremely fine particles of carbon which cannot beremoved in the desludger are separated from the oil, and the completelypurified oil is returned to the lubricating system of the engine to belu cated. I

Although-the present invention has been described in connection with afew preferred embodiments thereof, variations and modifications may beresorted to by those skilled in the art without departing from theprinciples of the pres- V 40 and the like through the lubricating systemof tions to connect said cham ferent from lubricating oil, providedthere is a substantial and snfiicient difference between the specificweight and frictional coefilcient of the substances to be separated fromeach other. I consider all of these variations and modifications 10 aswithin the true spirit and scopeoi the present invention as disclosed inthe present specification and defined by the appended claimsn Thepresent application is a continuation in partf of my copendingapplication Serial No.

{5 140,616, filed on May 4, 1937, for "Oil filter."

l. The method of purifying oil which comprises establishing a flow ofoil containing impurities including water, solid particles, gums,resins, tar

2'0 'and the like through the lubricating system of an engine,establishing a passage of periodically varying cross section anddirection between closesaid container, strips extending between said lyspaced inclined and conical surfaces completely filled by saidfiow tosubject the same to ac- 2'6 celeration and deceleration and to reversalof direction to retard the flow of impurities with respect to the flowof pure oil, temporarily trapping said retarded impurities at a largenumber 2 of points along said flow, slowly displacing said trappedimpurities downwardly by means of gravitational action, and permanentlytrapping said impurities at the lowest point of. said system topermanently withdraw them from the circulation whereby said fiow of oilis maintained substantially free from water and from the saidin'ipurities.

2. The method of-puriiying oil which'comprises establishing a fiow ofoil containing impurities including water, solid particles, gums,resins, tar

an engine, establishing a passage of periodically varying cross sectionand direction between close- --ly spaced corrugated conical surfacescompletely filled by said how to periodically change the magnitudeand-the direction of the velocity of all of said fiow thereby to retardthe fiow of impurities with respect to the flow of pure oil due 7 tothedifferential eflfect of acceleration and frictional resistance,separating said retarded flow 60 of impurities from the unretarded mainflow of relatively puroil, subjecting a portion of the oil thus treatedto filtration to remove the very fine remaining particles of impurities,and returning the filtered oil to the .main flow of oil,

whereby said fiow of oil is maintained substantially tree from waterand. from the said impurities. r A -3. In an oil purifier, thecombination which comprises a container, a plurality oi spaced conicalpartitions in said container dividing the same into a plurality ofsuperposed chambers, ports in the upper. and lower portio ofalternatepartiin series and to provide a channel or periodicallyreversed direc- 35 tion, means for conducting oil containing imspurities through said 'channel tow-i186 D -ration of said 011 into afastenmoving stream of in- ,creasinglypure oil and into a retardedstream of heavy impurities, ports in the lowermost por- 10 Ytion of saidpartitions 101-: the discharge or said- J w drawing treated and pure oilfrom said container.

retarded impurities, a sludge chamber in the lowermost portion of saidcontainer and in communication with said discharge ports for collectingsaid retarded impurities, and an outlet for with- 4. In an oil purifier,the combination which comprises a container, a plurality of cone-shapedmembers within said container and defining a plurality of passages,openings in the upper and lower portions of alternate members to-connect5 said passages and to-iorm a continuous channel the direction or whichis varied continuously and periodically, means for conducting oilcontaining impurities through said channel to cause separation or saidoil into a taster moving stream of increasingly pure oil and into aretarded stream of heavy impurities, sludge discharge ports in thecentral portionsmt said partitions for the -discharge 01 said retardedimpurities through members defining a plurality of passages, ports inthe upper and lower portions of alternate coneshaped members to connectsaid passages and to form a continuous channel, means for conducting oilcontaining impurities through said channel to cause separation 01 saidoil into a faster moving stream of increasingly pure oil and into aietarded stream or heavy impurities, sludge discharge ports in thecentral portion of said coneshaped members tor the discharge or saidretarded impurities y means of gravitational action, a sludge chamber inthe lowermost portion of said container, for collecting said impurities,a chamber in the top portion of said container for collecting pure oilsubstantially free from impurities, and an outlet for withdrawing thetreated and pure oil from said chamber.

6. In an oil purifier, the combination which comprises a container, aplurality of superimposed spaced conical partitions in said containerhaving their apexes extending downwardly, said partitions beingalternately provided with a central opening at the apex thereof and the'remainder or said partitions being provided with peripheral openingsand a central tunnel-shaped portion at the apex thereof, each of saidfunnels projecting through the central opening of the preceding conicalmember with sufllcient clearance tor the passage or oil therearound,means for supplyingoil containing impurities under pressure to the spacebetween the lowermost of of said partitions, means for withdrawingpurified 011 above the uppermost of said partitions, and asludge tubeinto which the lowermost or said tunnels projects ior conveyingimpurities to thevbottom oi. said container. 5, v

7. In an oil purifier, the combination comprising. a container, spacedpartitions ,in said container having incllnedsurfac areas, a pluralityof strips vertically extending on said partitions and dividing the spacetherebetween into passages of continuously varying direction, said aspartitions'terminating at the lower-portion theresaid passages, saidfunnels projectinglntoeach other for such depth and with suchclearance'that the length oi! the restricted passage area therebetweenwill ofler resistance to the flow of oil therethrough greater than theresistance to flow J 20 I prising a container, means for supplying oilconthrough said passages of continuously varying direction, and anoutlet for withdrawing treated and pure oil from said container.

8. In an oil purifier, the combination comprising a container, aplurality of conical members located in said container in spacedsuperposed relation and forming a plurality of passages, corrugations insaid conical members'to provide a periodically constricting andexpanding cross section for said passages, ports in the peripheralportions and a single port in the central portion of alternate conicalmembers to connect said passages to form a continuous channel, means forpassing 011 containing impurities through said passages, funnel-likeextensions associated with the lowermost portions of said passages forremoving impurities from said oil by gravitational action, and an outletfor withdrawing treated and pure oil from said container.

' 9. In an oil purifier, the combination comtaining impurities to anintermediate portion of said container, a plurality of conicalpartitions having corrugated surfaces located in said container abovesaid oil supply means, said corrugations on adjacent partitions beingoppositely disposed to provide continuously varying resistance to the,flow of oil therebetween, means for passing oil over said surfaces tocause separation thereof into a fast moving portion of increasingly pureoil and into a retarded portion of heavy impurities, means associatedwith the lowermost portion of every other one of said conical partitionsto convey the heavier and retarded impurities to the lower portion ofsaid container,

' and an outlet in the upper portion of said container for withdrawingtreated and pure oil therefrom.

10. In an oil purifier, the combination comprising a container, meansfor supplying oil containing impurities to an intermediate portion ofsaid container, a plurality of conical partitions having corrugatedsurfaces located in said container above said oil supply means, saidcorrugations being less pronounced and lower near the innermost portionof said partitions than near the peripheral portion, ports in theperipheral portions and a single port in the central portion ofalternate conical partitions to connect the spaces between saidpartitions to form a continuous channel, means for passing oil throughsaid channel to cause separation thereof into a fast moving portion ofincreasingly pure oil and into a'retarded portion of heavy impurities,means associated with the lowermost portion of every other one of saidconical partitions to convey the heavier and retarded impurities to thelower portion of said container, and an outlet in the upper portion ofsaid container for withdrawing treated and pure oil therefrom,

said partitions for conveying the heavier particles of said retardedflow to the lower portion of said container, and restricting meanswithin upward flow of the lighter constituents of the oil therethroughthan the downward flow of the heavier impurities.

MORITZ GAERTNER.

' said funnels providing a greater-resistancelto the ,5

